Air-separator



T. J. STURTEVANT.

AIR SEPARATOR.

APPLICATION FILED FEB. I6. 1920.

Patented July 5, 1921.

chamber.

UNITED STATES PATENT OFFICE.

VAN'I' MILL comrm, or CHUSETTS.

AIR-SEPARATOR.

I 0 all whom it may concern:

the following description, in connection with the accompanying drawings, is a specification, like characters on the drawings representing like parts.

The invention to be hereinafter described relates to air separators for grading materials. Separators of this type are usually provided with a fan for producing an upward current of air through a separating The materials to be graded are introduced into this upward current of air. The heavier particles ortailings gravitate downward through the upward moving air current, while the lighter particles or fines are carried along with the air current over into a collecting chamber. The tailings and fines are discharged from the separator through outlets communicating with the separating chamber and collecting chamber respectively. 4

In some cases the materials to be graded are introduced into the separator through the top thereof and gravitate downward to a distributer which throws the particles outward into the path of the upwardly moving air current. In, other cases, the materials to be graded are introduced pneumatically into the casing, and are thrown outward into the path of the rising air current.

One of the purposes of the present invention is to provide means positively to feed the materials to be graded into the path of the rising air current. In the present instance of the invention, the feeding-in means is constructed and arranged to conduct the materials from one side of the casing of the separator toward the center thereof.

Another purpose of the invention is to provide means for causing an air current to move upward through the separating chamber and thence downward through a passage and back upward to the separating chamher in a closed circuit, the construction be ing such that-the materials may be delivered into the path of the air current rising in the separating chamber.

Another purpose of the invention is to Specification of Letters Patent.

BOSTON, MASSACHUSETTS, A. CORPORATION OF MASSAe- Patented July 5,1921.

, Application filed February 16, 1920. Serial No. 358,983.

provide a rotary distributer which mayreceive the materials fed into the separator, said distributer being provided with afan which is rotated by the air current moving upward through the separating chamber. This fan may serve to impart rotation to the distributer to throw the materials outward under the influence of centrifugal force, and also this fan may serve to develop a whirl of the upwardly moving air current, so that the latter will move upward in a long spiral path and the materials may be thrown ra' dially outward and distributed in the path of the u wardly moving air current. Cer-. tain of the materials will be thrown farther outward than others by the centrifugal force effect of this whirl depending-upon the relative weight or other characteristics of the particles. This will desirably spread the particles and tend to moving heavier particles from impinging upon and pulling down the lighter particles. As a consequence, the efliciency in separatingvmaterials is materially increased.

ith the aforesaid and other objectsin view, the character of the invention will be best understood by reference to the following description of one good form thereof shown in the drawing, wherein a separator embodying the invention is shown in vertical section.

Referring to the drawing, the separator shown therein as one good form of the invention, comprises a casing 1, in the present instance of the invention, including a lower conical wall 3 and an upper conical wall 5 meeting and diverging from their juncture for a purpose to be described. At the lower end of the lower conical wall 3 is a discharge outlet 7 for the lighter particles or fines. The top of the upper conical wall 5 may be provided with a. head 9. The casing described may be provlded w th suitable supporting means, in the present 1nsta1.ce, 1n the form of feet or brackets 11 which may be mounted on beams or other appropriate supports. Mounted within the casing described is an inner casing 18, in the present instance, comprising a lower conical wall 15 and an upper conical wall 17 meeting and divergin from their juncture. This inner casing divides the separator into a separating chamber 19, and a collecting chamber 21.

revent the downward Suitable means may be provided for causing an air current to move upward through the separating chamber and thence outward into the collecting chamber. This means, in the present instance of the invention, is in the form of a fan 23 comprising a series of vanes 25 secured to and projecting downward from a disk 27 secured to'a hub 29 mounted on a vertical shaft 31 projecting upward through and beyond the head 9 of the outer casing. This shaft may be ournaled in a lower bearing 33 carried by a sleeve 35 projecting downward from a bearing 37 on a bracket 39 mounted on the head 9 of the outer casing. Fast on the upper end of the shaft 31 is a pulley 11 which may be driven by a belt from any suitable source of power. The lower bearing 33 may be lubricated by an oil cup 43 connected by a pipe 45 with said bearing. Opposed to the fan 23 is a ring plate 47 mounted on the upper edge of the conical wall 17 of the 1nner casing and opposed to the disk 27 of sa1d fan.

The construction is such that rotation of the fan will develop an air current upwardly through the separating chamber 19 and whirl the same thence outward between the ring plate 47 and the'disk 27 of the fan. This air current will whirl in a splral path upward through the collecting chamber.

Suitable means may be provided for con-' ducting the air current from the collecting chamber back to thelower end of theseparating chamber. To accomplish this, in the present instance of the invention, the head 9 of the outer casing may be provlded with an opening 49 communicating with a throat 51 which may be connected to a pipe having a horizontal portion 53 projecting outwardly from the casing, a vertical portion 55 projecting downward, along the casing toward the bottom thereof, and a curved portlon 57 projecting inward toward the casing and meeting an inclined pipe 59 WlllCh may project through the casing and be connected with the lower conical wall 15 of the separating chamber. I

The construction is such that the fan 23 will draw the air current upwardly through the separating chamber and from the pipe supplying air to this chamber, and-as the air is forced by the fan into the collecting chamber, the air in the upper portion of this chamber will flow into the pipe where it will pass to the separating chamberand to the fan again.

As stated, one of the purposes of the invention is to provide means for positively feeding the materials to be graded into the separating chamber. This means, in the present instance of the invention, comprises a hopper 61 communicating with a tube 63 projecting horizontally across the outer casing and secured thereto conveniently at the juncture of the lower conical wall 3 and the conveniently centrally 0 upper conical wall 5 thereof. 'ine tube 63 may have a lateral opening therein comneck 65 located the separating chamber. Suitable feeding means may be mounted in the tube 63, in the present instance, in the form of a screw conveyer 67 on a shaft 69 journaled in bearings 71 and 73 at the opposite ends of the tube 63. Mounted on one end of the shaft 69 is a pulley 75 which may be driven by a belt from any suitable source of power. The construction is such that materials to be graded may be introduced into the hopper 61 and positively fed by the screw conveyer-67 to the neck 65. The materials will pass thence into the separating. chamber.

Suitable means may be provided for distributing the materials into the path of the air current rising upward through the separating chamber. This distributer, in the present instance of the invention, comprises a plate or table 77 mounted on the upper end of a stub shaft 79 j ournaled in a ste bearing 81 carried by brackets 83 mounte on and municating with a delive projecting inwardly from the lower conical wall 15 of the inner casing. The step bearing.may be lubricated by an oil cup 85 connected by a pipe 87 with said bearing.

Suitable means may be provided for rotating the distributer table 77, in the present instance, this means comprises a fan 89 having vanes 91 securedto the under side of the distributer table 77, and preferably projecting outward therefrom toward the lower conical wallof the inner casing.

The air current rising in the separating chamber will move past the distributer fan 89 and cause the same to rotate. The materials to be graded issuing from the neck 65 will drop onto the distributer table, and the rotation thereof will cause the materials to be thrown outward under the influence of centrifugalforce into the path of the rising air current. The distributer fan89 will also produce a whirl of the air current generating a centrifugal force which will further tend to cause the particles to move outward and be distributed-into the path of the rising air current. As stated, certain of the particles will move outward farther than others under this influence, depending on the relative weight or other characteristics of the particles, and this separation of the particles will tend to prevent the heavier particles or tailings from impinging upon and pulling downward the lighter particles.

' Suitable means may be provided further to contribute to the whirl effect of the air current as it moves upward through the separating chamber. To accomplish this, in the present instance, the pipe 59 leading to the separating chamber may be provided with rifling or spirally disposed ribs 93 projecting mward somewhat from the inner surface tion, is in the form of a valve 103 mounted ered therefrom through an outlet '95. This outlet may be provided with a valve or gate 97 which may be pivotally mounted in the outlet 95 and may be urged toward closed position by a weight 99 on an arm 101 projecting from said gate.

The construction is such that after a suflicient weight of mate rials has collected on the gate, it will overcome the counterbalance weight 99 and cause the gate to open to discharge the materials through the outlet 95. Thereupon, the gate willbe automatically closed by the weight 99.

Suitable means may be provided to regulate the strength of the air current. This means, in the present instance of the invenin the vertical pipe 55 and provided with a control handle 105.

In the operation of the separator, the materialsto be graded may be introduced into the hopper 61 and fed by the screw conarating chamber. The heavier particles or tailings will gravitate downward through the risin air current through the pipe 59 v and be discharged through the outlet 95 as described. The lighter particles will be whirled with the rising air current upward w through the separating chamber and be directed inward by the conical wall. 17 to ward the axis of the fan. They will move thence outward past the vanes of the fan between the ring plate 47 and the disk 27 of said fan. The lighter particles will be thrown outward under .the influence of 'centrifugal force generated by the whirling air current into the enlarged space in the collecting chamber at "the juncture of the lower and upperconical walls of the outer casing. The lighter particles may impinge upon the upper conical wall, and be guided thereby to the lower conical wall, and flow downward along the same and be discharged through the fines outlet '2'. The air current may whirl upward through the collecting chamber and be directed toward the opening 49 in the head of the outercasing, and ass thence through the pipes53, 55, 5 7, an back to the separating chamber.

The fan is desirably located adjacent the chamber, thence enlarged space between the outer and inner casings afforded by their diverging walls. The lighter particles are thus whirled by the fan outward a substantial distance and have op'portunity to leave and gravitate downward through the air current before the latter is directed inward and passes up through the opening at the top of the separator.

It will be understood that the invention is not limited to the specific embodiment shown, and that various deviations may be arating chamber into the collecting cham-' her, a pipe for conducting the air current from the collecting chamber to the separating chamber, means for feeding materials down into the separating chamber, a

rotary distributer for receivlng the materials from said feed means and delivering the same into the path of the upward mov- 1 ing air current, and a fan rotated by said air current for rotating said distributer.

2. An air separator for grading materials, comprising, in combination, a casing having a collecting chamber and a separating chamber, a by-pass conduit leading from the upper ortion of the collecting own and up to the lower end of .the separating chamber, meansfor causing an air current to circulate through the conduit, up through the separating chamber to the collecting chamber and from the latter to the conduit, means posltively to feed materials to be graded into the separating chamber, and a rotary dlstributer within the inner chamber for throwing the materials outwardly into the path 0 the rising air current, the collecting chamber.

rials, comprising,'in combination, a casing having a collecting chamber and a separating chamber, a by-pass conduit leading from theupper portion of the collecting chamber to the lower end of the separatmg chamber, means for causing an air current to circulate through the conduit, vu through the separating chamber to the co ectmg chamber and from the latter to the conduit,

means to feed materials to be graded into I the up er end of the separating chamber,

a distri uter within the separating chamber beneath the feed means for distributlng the materials to be graded into the path of the rising 7 air current, said separating chamber' being constructed to direct the materials from 'the conduit.

heavier materials downwardly into the conduit, and means for removing the heavler 4. An air-separator for grading materials, comprising, in combination, a casinghaving therein a separating chamber and a collecting chamber,"a conduit leading from the upper portion ofthe. collecting chamber,

thence downward and upward to the lower.

end of the separating chamber, means for causing an air current to circulate through the conduit, up :through the separating v chamber to the collecting chamber and from separating chamber for throwin the materials outwardly into the path 0 the using the latter to the conduit, means to feed materials to .be graded into the separating chamber, a rotary distributer within the air current, said separating chamber being constructed to direct the heavier particles downwardly into the conduit, and means for removing theheavier' articles from:

the conduit, said collecting c amber having an outlet for deliveringthe fines therefrom, and said conduit having an. outlet for delivering the tailings therefrom.-. 5. An air separator for grading mate- -"rials, comprising, in combination, a casing having therein a separating chamber and a collecting chamber, a conduitleadingfrom the upper portion of the collecting chamber, thence down and up to the lower end of the separating chamber, said separating chamber being closed to the collecting chamber at its lower end and communicating therewith at its upper end, means for forcing air from the up or portion of the collecting chamber throng the conduit upwardly through the upper .conica from their juncture, an inner easing withins the outer casing and having a lower conical wall and anupper conical wall meeting and diverging from theirjuncture, said casing, forming a separating chamber within the inner casing and a collecting chamber surrounding'the separating chamber, means to cause an air current to circulate upward through said separatin chamber into said collecting chamber, an means to feed materials to-be ad'ed down into the separating chamber in the path of the air current moving upwardly therein.

7 An air separator for grading materials, comprislng, 1n combmatlon, a casmg having a separating chamber and a collecting chamber therein, a conduit leading from the upper end of the collecting chamber to the lower end of the separating chamber, a fan for causing air current to circulate through said separating chamber, collecting chamber and conduit, means to feed materials to be graded into the separating chamber, and arotary distributer for receiving materials and whirling the same outward into the separating chamber, said distributer having a fan for rotating the same driven by the air current moving upward through the separating chamber.

8. An air separator for grading materials,

comprising, in combination, a separating chamber, means to introduce materials to be graded 1 nto sald separat ng chamber, means for causing an air current to move upwardly in the separating chamber, a rotary distributer havin a material supporting area of substantia extent: for receiving thev materials thereon and throwing thesame outward under the influence of centrifugal force, and means 'operatively connected with the rotary distributer and driven by the upward movement of the air current to rotate the distributer. I

9. An air separator for grading materials, comprising, in combination, an outer casing, an mner casing dividing the outer.

casing into a separating chamber and a collecting chamber, means for causing air current to move upward through said separatng chamber a bearing mounted in said separating chamber, a rotary distributer mounted in said bearing, a fan for rotating said distributer and actuated by the air current moving upward in said separating chamber, and means to feed the materials to be graded to said rotary distributer, that they may-be whirled by the latter outwardly in theseparating chamber in the path of the an current moving upwardliy therein.

10. An air separator forgra ing materials,comprising,1n combination, a separating chamber, means for causing an air current to move upwardly therein, a rotary distributer comprlsing a plate mounted in said separating chamber, and having a material supporting area, a fan for rotating said table actuated by the air current moving upward in said separatin chamber, and means to feed materials to ie graded onto said table.

11. An air separater for grading materials, comprising, in combination, aseparatlng chamber and a collecting chamber, a pipe leading from the upper end of said collecting chamber to the lower end of said I separating chamber, means for causing an air current to circulate through said separating chamber, collecting-chamber and said pipe, the latter having spiral ribs projecting m- Wardly therefrom for causing the airto whirl as it enters the separatlng chamber,

a rotary distributer mounted in said chamber, a fan for rotating said distributer actuated by the air current moving upward in said separating chamber, and means for feeding materials to be graded into said separating chamber to said distributer, that they may be thrown outward by the latter intothe: separating chamber under the influence of centrifugal force.

12. An air separator for grading materials, comprising, in combination, a casing hav-' ing a separatlng chamber and a collecting chamber therein, a fan located "above said separating chamber a substantial distance said separatin means to feed materials to be graded into said separating chamber beneath said fan and above said distributer.

13. An air separator for grading materihaving a separating chamber and a collecting chamber therein, a pipe leading from the upper end of the collecting chamber around the casing and upward to the lower end of the separatingchamber, said casing having an outlet for delivering fines therefrom, and said pipe having'an outlet for delivering tailings therefrom, means for causing an air current to circulate through .als, comprising, in combination, a casing said'separating chamber,collecting chamber and pipe in closed circuit, an air driven rotary distributer in said separating chamoer; and means to feed materials to be grao ed to said rotary distributer.

In testimony whereof, I have signed my name to this specification.

THOMAS J, STURTEVANT. 

